Astronomer's Toolbox

Diffuse Background

Try This!

Fill in the crossword puzzle below based on your knowledge of what makes up the diffuse background.

Enter your answer for each clue in the box provided for you. At any time, you can press the button (found below all the clues) to add your answers to the crossword. To change a single word, go back to where you entered the word in the box, delete the incorrect text, enter the new word, and press the button to have it show up in the puzzle. Changes will only show up if they are done this way. They will not show up if the change is just made in the puzzle. If you need to start over, press the erase button. This will clear the entire puzzle.

If the computer beeps at you and refuses to accept any more input to an answer, you have entered more than the allowable number of letters for that answer!

Do not include spaces or hyphens in your answers.

Across

1. Gas in our Milky Way _________ creates a large part of the gamma ray diffuse background. (6 letters)

4. Negatively charged particles involved in pair-annihilation, a source of diffuse background radiation. (9 letters)

6. Hot, young stars emit this, which helps heat the diffuse X-ray background. [2 words] (11 letters)

10. Very bright, distant objects that make up over 60% of the diffuse X-ray background at energies of 1-2 keV. (7 letters)

11. Positively charged particles involved in pair-annihilation, a source of diffuse background radiation. (9 letters)

12. X-ray satellite that took deep observations of the X-ray background. (5 letters)

13. Al-26 emits this, which can then be detected by the COMPTEL gamma ray instrument. (9 letters)

14. Gamma rays and X-rays are both part of the electromagnetic __________. (8 letters)

16. Future gamma ray observations may be able to tell us how this evolved. (6 letters)

Down

1. Highest energy radiation given off by the diffuse background. [2 words] (9 letters - plural form)

2. Some of the diffuse background radiation comes from within our galaxy, and some is _____________. (13 letters)

3. An astronomical picture, such as the diffuse gamma ray background seen by the EGRET instrument. (5 letters)

5. Stellar explosion that can heat gas in the diffuse background to 1 million degrees, or more. (9 letters)

6. The low-energy X-ray background comes from hot gas filling some of the space between these astronomical objects. (5 letters)

7. Science that studies the diffuse background, as well as stars, planets, and all other objects in space. (9 letters)

8. The diffuse background can be seen in many types of _________ invisible to the human eye. (5 letters)

9. One type of energy emitted by the diffuse background. (4 letters)

15. These interact with interstellar gas to make the diffuse background glow at high energies. [2 words] (10 letters)

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Solution

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This activity was developed by Cheryl Carter, Bladensburg High School, Bladensburg, MD